Document Type : Research Paper

Authors

• shahriar khaledi ¹
• Esmaeil Bakhshi ²
• Mahmoud Ahmadi ³
• Abbasali Dadashi Roudbari ⁴

¹ Department of Natural Geography, Faculty of Earth Sciences, Shahid Beheshti University, Tehran, Iran

² PhD Student in Meteorology, Zanjan University, Zanjan, Iran)

³ Associate Professor of Meteorology, Faculty of Earth Sciences, Shahid Beheshti University, Tehran, Iran)

⁴ Postdoctoral Student, Ferdowsi University of Mashhad, Mashhad, Iran) Dadashiabbasali@gmail.com

Abstract

From urbanization, the phenomenon of the urban temperature island follows which the city rises and increases from energy to cool. In this research, the role of local factors in the creation and development of heat islands in the city of Ahvaz during the hot period from 2000 to 2015 was investigated using Landsat 7 and 8 satellite data. In order to evaluate the biophysical changes of the land surface in Ahvaz city, the changes of vegetation difference indices were taken by Tokanga-Tag threshold method. By using the kriging method and the low speed zones of Ahvaz, the thresholds of the closest and maximum temperature of Ahvaz city, it appears that this change can cause a change in the local climate. The results of Moran's spatial autocorrelation are a confirmation of the lack of spatial correlation of ground surface temperature in Ahvaz. The evaluation of the northern maps showed that as we move from the southern regions to the northern regions, the temperature increases due to the increase of green space and the increase of barren lands. There is a sharp temperature difference between the central and suburban areas of the city, because of the establishment of industrial companies, District 8 has formed the most stable islands in this area of the city. Residential areas have had less impact on the creation and expansion of thermal islands than industrial and barren areas.

Highlights

rom urbanization, the phenomenon of the urban temperature island follows which the city rises and increases from energy to cool. In this research, the role of local factors in the creation and development of heat islands in the city of Ahvaz during the hot period from 2000 to 2015 was investigated using Landsat 7 and 8 satellite data. In order to evaluate the biophysical changes of the land surface in Ahvaz city, the changes of vegetation difference indices were taken by Tokanga-Tag threshold method. By using the kriging method and the low speed zones of Ahvaz, the thresholds of the closest and maximum temperature of Ahvaz city, it appears that this change can cause a change in the local climate. The results of Moran's spatial autocorrelation are a confirmation of the lack of spatial correlation of ground surface temperature in Ahvaz. The evaluation of the northern maps showed that as we move from the southern regions to the northern regions, the temperature increases due to the increase of green space and the increase of barren lands. There is a sharp temperature difference between the central and suburban areas of the city, because of the establishment of industrial companies, District 8 has formed the most stable islands in this area of the city. Residential areas have had less impact on the creation and expansion of thermal islands than industrial and barren areas

Keywords

• urbanization
• Urban Heat Islands
• Ahvaz. Moran'
• s spatial autocorrelation
• Kriging method

Main Subjects

• Climatology